Nautical area scattering coefficient (NASC) data

The NASCData model data gives the NASC for each acoustic channel or Layer, and ESDU, PSU or Stratum.

Details

Variable	Description	Unit	Data type	Example
EDSU	Unique elementary distance sampling unit (EDSU/Log) identifier	None	Character	"2020821/2020-04-24T03:51:26.000Z"
Channel	Unique NASC depth channel identifier	None	Character	"2"
Beam	Unique Beam identifier	None	Character	"38000/2"
AcousticCategory	The acoustic category	None	Character	"HER"
Frequency	The acoustic frequency of the Beam	hertz	Numeric	38000
NASC	The nautical area scattering coefficient.	m^2/nmi^2	Numeric	59.24813
MinChannelDepth	The minimum depth of the depth Channel	m	Numeric	0
MaxChannelDepth	The maximum depth of the depth Channel	m	Numeric	10
NASCWeight	The LogDistance of the EDSU	None	None	0.1
ChannelReferenceType	Unique ChannelReference identifier	None	Character	"P"
ChannelReferenceDepth	The depth of the ChannelReference origin. 0 for pelagic channels. Not yet given for bottom channels, as BottomDepth is not yet defined for NMDEchosounder data	m	Numeric	0
ChannelReferenceTilt	The tilt angle of the beam, where 180 is vertically downwards and 0 is vertically upwards	degree	Numeric	180
Cruise	Unique Cruise identifier (see StoxAcousticFormat for output from AcousticDensity and StoxBioticFormat for output from SweptAreaDensity)	None	Character	"2021105"
EffectiveLogDistance	The effective length of the EDSU	nmi	Numeric	0.09
DateTime	UTC time at start of the EDSU or Station, stored as POSIXct	ISO8601	Character	2020-09-09T01:02:03.456Z
Longitude	Longitude at start of the EDSU or Station	degree east	Numeric	62.5
Latitude	Latitude at start of the EDSU or Station	degree north	Numeric	5.1

See also

This data type is produced by NASC. NASCData is used in SumNASC with output SumNASCData and MeanNASC with output MeanNASCData. See DataTypes for a list of all StoX data types produced by RstoxBase